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DTC P0300-P0304 (LDK With Turbocharger)

DTC P0300-P0304 (LDK With Turbocharger)

Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• Diagnostic Procedure Instructions provides an overview of each diagnostic category.


DTC Descriptors

DTC P0300

Engine Misfire Detected

DTC P0301

Cylinder 1 Misfire Detected

DTC P0302

Cylinder 2 Misfire Detected

DTC P0303

Cylinder 3 Misfire Detected

DTC P0304

Cylinder 4 Misfire Detected

Circuit/System Description

The engine control module (ECM) uses information from the crankshaft position sensor and the camshaft position sensors in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM is able to detect individual misfire events. A misfire rate that is high enough can cause 3-way catalytic converter damage. The Malfunction Indicator Lamp (MIL) flashes when the conditions for catalytic converter damage have been fulfilled. DTCs P0301 to P0304 correspond to cylinders 1 to 4. If the ECM can determine that a certain cylinder is misfiring, the DTC for the cylinder will be activated, and the corresponding fuel injector will be disabled. The ECM will re-activate the fuel injector after 3 revolutions of the crankshaft during which misfiring no longer occurs. The ECM will re-activate the fuel injector after 6 revolutions of the crankshaft during which misfiring no longer occurs, given that the vehicle has a manual gearbox.

Conditions for Running the DTC


• DTC P0010, P0013, P0014, P0016, P0017, P0018, P0019, P0020, P0021, P0023, P0024, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0335, P0336, P0606, P0641, P0651, P1516, P2101, P2122, P2123, P2127, P2128 or P2176 is not set.

• When DTC P0315 is set, the engine speed must be more than 1,000 RPM.

• Engine run time is more than 2 crankshaft revolutions.

• The engine speed is between 450-6,600 RPM.

• The engine coolant temperature (ECT) is between -7 and +130°C (+19 and +266°F).

• When the startup ECT is colder than -7°C (+19°F), this diagnostic will be delayed until the ECT is warmer than +21°C (+69°F).

• The fuel level is more than 10 percent.

• The ECM is not in fuel shut-off, or decel fuel cut-off mode.

• The electronic brake control module (EBCM) and the traction control system (TCS) are not active or detecting rough road.

• An automatic transmission shift with a throttle position more than 95 percent is not occuring.

• The power management is not active.

• Excessive drive wheel slip is not detected.

• DTCs P0300 through P0304 run continuously when the above conditions exist for greater than 1,000 engine revolutions. 200 revolutions after the first failure.


Conditions for Setting the DTC

P0300

The ECM is detecting a crankshaft speed change indicating a random misfire is occuring that exceeds mandated emission level standards or is at catalytic converter damaging levels.

P0301, P0302, P0303, P0304

The ECM is detecting a crankshaft speed change indicating a single cylinder misfire is occuring that exceeds mandated emission level standards or is at catalytic converter damaging levels.

Action Taken When the DTC Sets


• DTCs P0300-P0304 are Type B DTCs.

• When the MIL is flashing the fuel injector may be disabled for the misfiring cylinder to protect the catalytic converter.


Conditions for Clearing the DTC


• DTCs P0300-P0304 are Type B DTCs.

• The DTC must run and pass under the same operating conditions that were present when the DTC failed.


Diagnostic Aids


• A misfire may only occur when the engine is operating under a load or when the engine is cold.

• A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect for the following possible sources:

- A tire or wheel that is out of round or out of balance

- Variable thickness brake rotors

- An unbalanced drive shaft

- Certain rough road conditions

- Transmission operation

- A damaged reluctor wheel

- A damaged accessory drive component or belt ; remove the belt and safely operate the engine to evaluate

• High resistance in the injector circuits can activate a diagnostic trouble code related to a misfire without activating a diagnostic trouble code related to an injector. Test for high resistance in the injector circuits for the affected cylinder if you suspect a problem.

• If the condition is intermittent, observing the scan tool IC Circuit Test and Fuel Injector Circuit Test Status parameters may help isolate the condition. The circuit test status parameters will change from OK or Not Run to Malfunction if a condition exists.

• A condition in the heated O2 sensor (HO2S) heater control circuits may set a DTC P0300.


Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference


• Circuit Testing

• Connector Repairs

• Testing for Intermittent Conditions and Poor Connections

• Wiring Repairs


DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools


• J 26792 Spark Tester

• For equivalent regional tools, refer to Special Tools .


Circuit/System Verification


1. Engine idling at the normal operating temperature.

2. If there is abnormal engine noise, refer to Symptoms - Engine Mechanical .

3. Verify that no other DTCs are set.

4. If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .

5. Observe the scan tool misfire parameters for cylinders 1 to 4. The number of misfires should not increase.

6. Engine idling, perform the Cylinder Power Balance test with a scan tool to isolate the misfiring cylinder. The engine speed should change when each injector is disabled.

7. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.


Circuit/System Testing


1. Verify the following conditions do not exist:

• Vacuum hose splits, kinks, and incorrect connections

• Engine vacuum leaks

• Crankcase ventilation system for vacuum leaks

• Fuel pressure that is too low or too high-Refer to Fuel System Diagnosis .

• Contaminated fuel-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

• Exhaust system restricted-Refer to Restricted Exhaust .

• If you find any of the above conditions, repair as necessary.

2. Ignition OFF, remove the T8 ignition coil of the misfiring cylinder, leaving the electrical connector connected.

3. Inspect the ignition coil boot, verify that the following conditions do not exist:

• Holes

• Tears

• Carbon tracking

• Oil contamination

• Water intrusion

• If you find any of the above conditions, repair as necessary.

4. Install the J 26792 Spark Tester to the boot of the appropriate T8 ignition coil and ground.

5.
Note

An erratic or weak spark is considered a no spark condition.


Attempt to start the engine and observe the J 26792 Spark Tester. The spark tester should spark.

6. If there is no spark, refer to Electronic Ignition System Diagnosis for diagnosis of the T8 ignition coil.

7. Ignition OFF, remove the spark plug from the misfiring cylinder. Inspect the spark plug, verify that the following conditions do not exist:

• Gas, coolant, or oil fouled-Refer to Spark Plug Inspection .

• Cracked, worn, incorrectly gapped-Refer to Ignition System Specifications .

8. If you find any of the above conditions, replace the spark plug.

9. Exchange the suspected spark plug with another cylinder that is operating correctly.

10. Engine idling, observe the scan tool Current Misfire Counter parameters. The misfire should not follow the spark plug exchange.

11. If the misfire follows the spark plug, replace the spark plug.

12. Verify the following conditions do not exist:

• A lean or rich Q17 fuel injector-Refer to Fuel Injector Balance Test .

• An engine mechanical condition-Refer to Symptoms - Engine Mechanical .

• If you find any of the above conditions, repair as necessary.


Repair Instructions


• Ignition Coil Replacement

• Spark Plug Replacement


Repair Verification


1. Install any components that have been removed or replaced during diagnosis.

2. Clear the DTCs.

3. Turn OFF the ignition for 60 s.

4. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

5. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair Verification for DTC P0420. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .